The present invention relates generally to liquid purification systems and more particularly to a system for removing free oil from aqueous fluid mixtures utilized in industrial machining applications.
Industrial machining operations generally require the use of coolants to prevent damage to tools due to excessive heat. Typically, a coolant comprises an oil-in-water emulsion or an aqueous mixture wherein water is the continuous phase, oil is the disperse phase, and soap is the emulsifying agent.
The emulsion is stabilized by electro-mechanical forces which are weakened or destroyed by contaminants in the form of metallic ions, free oil and bacterial action. The primary culprit in coolant deterioration is free or "tramp" oil which must be removed to maintain the stability and equilibrium of the emulsion. Moreover, abrasive colloidal solids, often found suspended in the emulsion, cause a decline in the quality of the coolant and blockages in coolant filters.